Category: Permutations and Combinations

There are two identical red, two identical black, and two identical white balls.In how many different ways can the balls be placed in the cells (Each cell to contain one ball) shown above such that balls of the same colour do not occupy any two consecutive cells?

Hamad Permutations and Combinations 20/09/2024

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A. 15
B. 18
C. 24
D. 30
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A question paper had 10 questions. Each question could only be answered as true(T) of False(F). Each candidate answered all the questions, Yet no two candidates wrote the answers in an identical sequence. How many different sequences of answers are possible?

Hamad Permutations and Combinations 13/01/2022

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A. 20
B. 40
C. 512
D. 1024
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In how many different ways can the letters of the word ‘MATHEMATICS’ be arranged so that the vowels always come together?

Hamad Permutations and Combinations 12/12/2021

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A. 10080
B. 4989600
C. 120960
D. None of these

Using all the letters of the word “NOKIA”, how many words can be formed, which begin with N and end with A?

Hamad Permutations and Combinations 06/12/2021

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A. 3
B. 6
C. 24
D. 120
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A letter lock consists of three rings each marked with six different letters. The number of distinct unsuccessful attempts to open the lock is at the most__________?

Hamad Permutations and Combinations 26/11/2021

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A. 216
B. 243
C. 215
D. 729
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A question paper consists of five problems, each problem having three internal choices. In how many ways can a candidate attempt one or more problems?

Hamad Permutations and Combinations 21/11/2021

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A. 63
B. 511
C. 1023
D. 15
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Groups each containing 3 boys are to be formed out of 5 boys. A, B, C, D and E such that no group can contain both C and D together. What is the maximum number of such different groups?

Hamad Permutations and Combinations 13/11/2021

0

A. 5
B. 6
C. 7
D. 8
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Six points are marked on a straight line and five points are marked on another line which is parallel to the first line. How many straight lines, including the first two, can be formed with these points?

Hamad Permutations and Combinations 11/10/2021

0

A. 29
B. 32
C. 55
D. 30
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In a class there are 20 boys and 25 girls. In how many ways can a boy and a girl be selected?

Hamad Permutations and Combinations 27/09/2021

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A. 400
B. 500
C. 600
D. 20
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A boy has nine trousers and 12 shirts. In how many different ways can he select a trouser and a shirt?

Hamad Permutations and Combinations 20/09/2021

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A. 21
B. 12
C. 9
D. 108
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